Many of the mobile phones and PDAs (Personal Digital Assistants) have a built-in lens unit and camera function. In recent years, a compact lens unit has been introduced into the market, which incorporates an optical path control device such as a mechanical shutter and diaphragm, and a lens driving device to drive the lens for optical zooming and focusing.
The optical path control device is characterized by an increased size and weight of the drive section that includes a drive source such as a solenoid to drive the optical path control member such as a shutter blade. The lens driving device is generally installed on the opposite side of the lens with the optical axis sandwiched in-between, for the purpose of avoiding possible interference with the drive section of the optical path control device. Thus, because the center of gravity of the optical path control device is far away from the drive apparatus, there is a problem that the drive of the lens is apt to be unstable by the torsion resulting from the inertia of the optical path control device when the lens is driven. In addition to this problem, there has been a problem of poor space efficiency and failure of downsizing the lens unit because the drive section of the optical path control device and the lens driving device are installed on the opposite sides of the lens.
Patent Document 1: Unexamined-Japanese Patent Application Publication No. 2002-6364